ADLINK PCIe 7256 Industrial Digital I/O Board

Product Overview and Features

1.1 Core Features

Bus: PCI Express x1, plug and play;

16 channel lock relay output (Form-C/DPDT), can maintain output state when powered off; Onboard LED indicates relay status;

16 channel non-polar optocoupler isolated digital input; Jumper can choose AC filtering/unfiltered (DC) input mode; Support dry contact input; Isolation voltage 2500Vrms (channel to system);

Support COS (Change of State) interrupt, DI0 and DI1 can also be separately configured with rising edge interrupt;

Card ID dialing S1, distinguishing different cards when multiple cards are on the same host at the same time;

68 pin SCSI interface CN1 leads out all I/O; Support external LED (JP3/JP4);

Comes with isolation and 5V power supply, maximum output 170mA@40 ℃.

1.2 Typical Applications

Industrial switch control, external high-power relay drive, signal switching, laboratory automation, limit switch monitoring, contact status detection.

1.3 Key Electrical Specifications

Digital isolation input DI

Channel: 16 routes; Rated input current 10mA, maximum 50mA; supports up to 24V AC/DC;

Isolation: 2500Vrms channel system isolation; JP1 controls DI0-7, JP2 controls DI8-15, and the jumper selects AC filtering/DC (default DC without filtering).

Lock relay output DO

16 channel DPDT Form-C; Contact specifications: 125V AC/0.5A, 30V DC/1A;

The suction/release time is 3ms each; the contact resistance is 60m Ω; the insulation resistance is ≥ 1000M Ω @ 500VDC.

Physics and Environment

Size: 175mm × 107mm, PCIe half length card; Working temperature: 0-60 ℃; Storage -20~80 ℃; Humidity of 5-95% without condensation.

1.4 Software Support

PCIS-DASK: 32/64 bit kernel driver+SDK, supports Windows 7/8.1; Provide DLL, compatible with LabVIEW;

DOS environment provides C/C++function library; Drivers must be installed before installing the board.

Board hardware layout, connectors and jumpers

2.1 Components on PCB board

Identification name function

JP4 external LED connector

B JP3 external LED connector

C S1 Board ID 4-digit DIP dip switch

D JP2 DI8-15 AC/DC filter jumper

E JP1 DI0-7 AC/DC filter jumper

F CN1 68 pin SCSI I/O interface

2.2 CN1 68 pin SCSI connector

include:

Each relay circuit: NO (normally open), COM (common terminal), NC (normally closed);

DI0~DI15 isolated digital input; DICOM1 and DICOM2 are DI common terminals;

ISO5V isolated 5V output, ISOGND isolated ground.

2.3 Jumper JP1/JP2 Input Mode Settings

JP1 corresponds to DI0-DI7; JP2 corresponds to DI8-DI15;

Factory default: DC (non AC filtering, suitable for DC signals); Switch the jumper to the AC position to enable RC AC filtering and adapt to the AC input signal.

2.4 Board ID (S1 DIP dip code)

4-digit dip switch, 1=ON, 0=OFF; The ID value ranges from 0 to 15. In a multi card system, software relies on BoardID to distinguish between boards and avoid access conflicts.

2.5 External LED (JP3/JP4)

16 external LED channels can be connected for displaying relay status on the chassis panel;

The board is equipped with a 330 Ω current limiting resistor, and the forward voltage drop Vf of the LED must be less than 2V; pay attention to the polarity of the LED.

Hardware installation steps

Unpacking inspection: The accessories include PCIe 7256 board and quick start guide; Pay attention to anti-static measures, use anti-static bags and wristbands;

First install the driver software, then physically insert the card;

Turn off the host power, unplug the power cord, and open the chassis;

Align the gold finger of the board with the PCIe x1 slot and press it into place, then fix the baffle with screws;

Reinstall the computer case and power it on.

PCIe plug and play: Base address and IRQ interrupt number are automatically assigned by BIOS/system, without the need for jumper settings. If the system starts abnormally, investigate BIOS interrupt resource conflicts.

Register definition (low-level IO programming)

All registers are 16 bits wide and only allow 16 bit IO instructions to access, offset relative to the base address BASE:

Offset write function and read function

0x00 relay output CH0-CH7-

0x02 Relay Output CH8-CH15 Relay Readbacks CH0-CH15 Status

0x04- Isolation DI Input CH0- CH15

0x06 COS setting register COS latch register

0x08 Interrupt Control Register Interrupt Status Register

4.1 Relay output control register

Each channel of the latch relay occupies 2 bits:

DOx_S (set), DOx_R (reset);

(1,0) → SET, NO connects to COM;

(0,1) → RESET, NC connects to COM;

⚠️ Prohibit writing (1,1), relay status is unpredictable.

Read back register: bit=1 indicates relay SET; Bit=0 indicates RESET.

4.2 Isolated Digital Input Register (BASE+0x04 Read)

Bit x corresponds to DIx; 1=Input high level; 0=Input low level.

4.3 COS status change interrupt

COS setting register (0x06 write): bit set to 1, corresponding to DI channel open state change interrupt (both rising edge and falling edge triggered);

COS latch register (0x06 read): When a state transition occurs, the DI level is latched. After clearing the interrupt, the hardware automatically resets to zero, eliminating CPU polling.

4.4 Interrupt Control Register (BASE+0x08 Write)

Supports two sets of mutually exclusive interrupt modes, which cannot be turned on simultaneously:

Mode 1 COS Interrupt: An interrupt is triggered when the level of any DI channel that is turned on changes;

Mode 2 DI0/DI1 interrupt: only supports rising edge triggering, can choose DI0, DI1 single or dual path.

Register bit definition:

Bit0: COS_CLR (write 1 to clear COS interrupt)

Bit1: CHO_CLR (write 1 to clear DI0 interrupt)

Bit2: CH1_CLR (write 1 to clear DI1 interrupt)

Bit8: COS_int-IN enables COS interrupt

Bit9: CH0_Int-IN Enable DI0 rising edge interrupt

Bit10: CH1-INt-IN enables DI1 rising edge interrupt

4.5 Interrupt Status Register (BASE+0x08 Read)

Bit0=COS interrupt status; Bit1=DI0 interrupt state; Bit2=DI1 interrupt status; Simultaneously read back interrupt enable configuration bit.

It is illegal to open both COS Int-IN and CHO/CH1 Int-IN simultaneously.

Appendix A C/C++Library Functions in DOS

Provide a set of DOS environment driver libraries, with main APIs:

_7256Initialize: Initialize by scanning the PCIe 7256 card of the system to obtain the base address and interrupt, which must be called first;

_7256-DO: Output, control latch relay SET/RESET;

_7256-DO-Read_Sack: Read the current status of the relay;

_7256-DI: Read all 16 DI inputs;

_7256_SOS_Channel: Configure which DI channels to enable COS state change detection;

_7256_SOS_Latch: Read the DI data obtained from the COS latch;

_7256-IND_Control: Set interrupt mode (COS/DI0/DI1);

_7256_ GET_SRQ_Status: Read interrupt status;

_7256_SLR_SRQ: Clear the interrupt request flag.

Data types: U8, I16, U16, I32, U32, F32, F64, Boolean.